The van was owned by Avoyelles House of Mercy in Marksville.
The van, which was from Louisiana, had about 10 to 12 people inside, authorities said.
The Highway Patrol said two vehicles traveling north - a tractor-trailer and a auto - smashed into each other and then burst through a metal guardrail, slamming into another semitrailer and the southbound van carrying the children.
As for the extent of injuries, Superintendent of the Louisiana District of the United Pentecostal Church Kevin Cox, stated that Descant received several broken bones and multiple bruises.
"It's unbelievable. Everybody is in shock", Maxine Doughty, a member of the Marksville congregation, told the Star-Banner.
"It's not going to change the fact of what we do day in and day out under very hard circumstances", he said.
According to the Florida Highway Patrol, the van was struck by a tractor-trailer that had made contact with another vehicle and crossed over the median into southbound lanes. Sadly, five of those children did not survive the accident. He said the pastor's wife was among at least eight people who were injured and that his granddaughter was among the children killed.
Other drivers traveling north who were fortunate to get by the crash site say they couldn't believe what they saw as they drove past others who were at a standstill in the southbound direction. Riordan confirmed that the 12 occupants of the passenger van were traveling to Disney World.
"There's going to be families that need to be notified that their loves ones have perished", said Lieutenant Patrick Riordan.
Three of the dead children were students in the public school system.
Vinnie DeVita said he was driving south at the time and narrowly escaped the crash. The public schools in Marksville are still on winter break, with students off from classes until Wednesday. Dauzat said the schools will have grief counselors available for students and staff and plan to organize some sort of activity to "allow them to have an outlet".
The highway is a busy transportation corridor.
"We kept seeing these little explosions and fire", Nicole Towarek told the Gainesville Sun. 'The heat, it was insane'.